1. Field of the Invention
The present invention relates to a method of retrieving image information from a database, including retrieving an object image at high precision from an image filing apparatus storing a great amount of image data such as remotely sensed images (hereinafter simply called images), and capable of retrieving the information of an object within a displayed image with ease and at high precision.
2. Description of the Related Art
Conventional image retrieving methods include a retrieving method for a meteorological satellite (NOAA) image information database system, disclosed in the Technical Report of the Institute of Electronics, Information and Communication Engineers of Japan, Vol. IE87-90, 1987, pp. 36 to 43. According to this retrieving method, a keyword is first entered to an image filing apparatus to retrieve an image index (or directory) corresponding to the entered keyword and display it on a display device. The image index contains identification information composed of a file name, an apparatus name, date and the like represented by characters and numerals. In retrieving the image index, a plurality of indices stored in the image filing apparatus are read to select the index corresponding to an entered keyword. If the object information cannot be retrieved, another keyword or a combination of keywords is used to repeat the above-described procedure.
A retrieval language called a Structured Query Language (SQL) has been provided as a computer software tool for a relational database, which language can be used with the above-described retrieving method using indices.